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Deployment project, environment building

Detailed content

1. Guide package

2.web > > index.jsp web > > login.jsp web > > success.jsp

1) web > > index.jsp

$Title$ login

2) web > > login.jsp

Login # msg {color: red;} account: password:

3) web > > success.jsp

The user Center welcomes you to return and log in again.

3.constant > > Con

Save user login information in package constant; import java.io.Serializable; public class Con implements Serializable {/ / session public static final String USER = "user";}

Entity > > User

Package entity; import java.io.Serializable; public class User implements Serializable {private int id; private String userName; private String passWord; public User (int id, String userName, String passWord) {this.id = id; this.userName = userName; this.passWord = passWord;} public User () {} public int getId () {return id } public void setId (int id) {this.id = id;} public String getUserName () {return userName;} public void setUserName (String userName) {this.userName = userName;} public String getPassWord () {return passWord;} public void setPassWord (String passWord) {this.passWord = passWord;}}

4.resources > > prop.properties

DriverClassName=com.mysql.cj.jdbc.DriverurlName=jdbc:mysql://localhost:3306/myjdbc?characterEncoding=utf8&useSSL=false&serverTimezone=UTCuserName=rootpasswordName=root

5.utils > > JDBCUtils

Package utils; import java.io.IOException;import java.io.InputStream;import java.sql.*;import java.util.Properties; / * JDBC utility class * / public class JDBCUtils {/ / declare the path static String driverClass; static String url; static String user; static String password of the driver / * static code block will only be executed once when the class file is loaded. The code of registration driver will be implemented by static code block * / static {/ / create attribute set object Properties prop = new Properties () / / read the data in the file into the property set try {/ / prop.properties InputStream is = JDBCUtils.class.getClassLoader () .getResourceAsStream ("prop.properties"); prop.load (is);} catch (IOException e) {e.printStackTrace () } / / get value driverClass = prop.getProperty ("driverClassName") for key; url = prop.getProperty ("urlName"); user = prop.getProperty ("userName"); password = prop.getProperty ("passwordName"); try {/ / load driver Class.forName (driverClass) } catch (ClassNotFoundException e) {e.printStackTrace ();}} / * encapsulates the method of obtaining resources: Connection connection interface object * / public static Connection getConnection () throws SQLException, ClassNotFoundException {/ / get connection Connection connection = DriverManager.getConnection (url, user, password); return connection } / * Encapsulation method for releasing resources * / public static void close (Connection connection, Statement statement, ResultSet resultSet) {try {if (resultSet! = null) {resultSet.close ();}} catch (SQLException e) {e.printStackTrace () } / / call the method that has already implemented the function directly using close (connection, statement);} / * reload a code that releases resources to release two resources * / public static void close (Connection connection, Statement statement) {try {if (statement! = null) {statement.close () } catch (SQLException e) {e.printStackTrace ();} try {if (connection! = null) {connection.close ();}} catch (SQLException e) {e.printStackTrace ();}

6.servlet > > UserServlet

Package servlet; import constant.Con;import service.UserService;import service.impl.UserServiceImpl;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException; @ WebServlet (name = "user", urlPatterns = "/ user") public class UserServlet extends HttpServlet {private UserService userService = new UserServiceImpl () Override protected void service (HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {/ / 1. Set the request character set to utf-8 req.setCharacterEncoding ("utf-8"); / / 2. Get the request parameter method, and use different methods to process business String method = req.getParameter ("method") according to the value; if (method.equals ("login")) {this.login (req, resp);}} / / login method private void login (HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {/ / 1. Get the account number and password String userName = req.getParameter ("userName"); String passWord = req.getParameter ("passWord"); / / 2. Call the method of service to process login boolean result = userService.checkUser (userName, passWord); if (result) {/ / true indicates login success / / forward jump success page / / req.getRequestDispatcher ("/ success.jsp") .forward (req, resp) / / save the user information in the session domain object req.getSession (). SetAttribute (Con.USER, userName); / / redirect the successful jump page resp.sendRedirect (req.getContextPath () + "/ success.jsp") } else {/ / false login failed, return login page req.setAttribute ("msg", "account password mismatch"); req.getRequestDispatcher ("/ login.jsp") .forward (req, resp);}

7.service > > UserService service > > impl > > UserServiceImpl

Package service; public interface UserService {/ / judge whether login is successful or not boolean checkUser (String userName, String passWord);} package service.impl; import dao.UserDao;import dao.impl.UserDaoImpl;import entity.User;import service.UserService;import utils.JDBCUtils;import java.sql.Connection;import java.util.List; public class UserServiceImpl implements UserService {private UserDao userDao = new UserDaoImpl () @ Override public boolean checkUser (String userName, String passWord) {/ / connection object Connection connection = null; try {/ / 1. Get the database connection connection = JDBCUtils.getConnection (); / / 2. Call the dao method to query data List users = userDao.findUserByUserNameAndPassWord (connection, userName, passWord); / / 3. Return the success and failure flag if (users.size () > 0) {return true;} else {return false;}} catch (Exception e) {e.printStackTrace (); return false;} finally {JDBCUtils.close (connection, null) based on the query result }}}

8.dao > > UserDao dao > > impl > > UserDaoImpl

Package dao; import entity.User;import java.sql.Connection;import java.util.List; public interface UserDao {/ / query the database according to the account password and return the result set List findUserByUserNameAndPassWord (Connection connection, String userName, String passWord);} package dao.impl; import dao.UserDao;import entity.User;import utils.JDBCUtils;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.util.ArrayList;import java.util.List Public class UserDaoImpl implements UserDao {@ Override public List findUserByUserNameAndPassWord (Connection connection, String userName, String passWord) {/ / send sql statement object PreparedStatement statement = null; List userList = new ArrayList (); try {connection = JDBCUtils.getConnection (); / / get Statement object statement = connection.prepareStatement ("select * from user where username =? And password =? "); statement.setString (1, userName); statement.setString (2, passWord); ResultSet rs = statement.executeQuery (); while (rs.next ()) {User user = new User (); int id = rs.getInt (1); String username = rs.getString (2) String password = rs.getString (3); user.setId (id); user.setUserName (username); user.setPassWord (password); userList.add (user);} return userList;} catch (Exception e) {e.printStackTrace (); return userList } finally {JDBCUtils.close (null, statement, null);} login implementation

1. Home page index.jsp

two。 Incorrect login to login.jsp

3. Log in to login.jsp correctly

4. Log in to success.jsp successfully

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